Method of and apparatus for forming tire and the like tubes



May i, 192s.

J. w. AUM'ANv METHOD OF AND APPARATUS FOR FORMING TIRE AND THE LIKE TUBES @attested l, 192,55,

unirse sra'rss PATENT lorries.

Jenn W. Annan, or RACINE, WISCONSIN.

METHOD OF AND. AF-PARATUS FOR FORMING TIRE AND THE'LIKE TUBES.

Application filed May 17,

rThis invention relates to certain improvements in the method of and apparatus for forming tire and the `like tubes; and the nature and objects of the invention will be readily recognized and understood by those skilled in the art involved in the light of the following explanation and detailed description of the accompanying drawings illustrating what I at present consider to be the preferred expressions and eu'ibodiments of the invention from among others of which the invention is capable Within the spirit and the scope thereof.

n certain methods ofy manufacturing tire r tubes, the tubes are formed on a cylindrical or tubular mandrel, generally referred to as a tube pole in the art, by Winding a sheet of unvulcanized rubber around and onto the mandrel, and then securing the rubber sheet in tube forming position thereon by Winding or Wrapping a band or strip of fabric spirally therearound and thereover with the convolutions'of the fabric band overlapping, after which the mandrel or pole carrying the rubber sheet so secured thereon, is vulcanized to produce a length of vulcanized cured tube. rihe vulcanized tube is removed by un- Winding the fabric band Wrapping and then stripping the tube from the mandrel. The tube thus formed is next prepared for splicing or joining the ends thereof together to complete the endless, annular tire or inner tube, by roughing the opposite ends thereof, one end on the inside and the opposite end on the outside, for a distance to cover the overlapped -end portions of the tube in the splice. The end of thetube roughened on the outside is then inserted in the end roughened or the inside, u suitable cement or other medium having been previously applied to the roughened tube ends, and the overla pped tube ends are then vulcanized or otherwise suitably secured together to forni thc splice and provide the endless annular tire tube, in accordance with any of the usual methods familiar in this art for splicing or vulcani/5* ing the ends of tire or other tubes together.

Generally, the operation of roughing or treating the ends of the tube after vulcanization or curing is carried out by meansof. a suitable bufiing Wheel or Wire scratch brush, and forms a distinct and separate step, usually performed by hand, in the retirees tube in anufactiufe as above out 1926, Serial No, l9,750.

lined, which step consumes time, lowers production While increasing the cost thereof, Vas Well'as rendering uniformity and eiliciency in the tube splices orjoints produced therewith diiiicult of attainment, due to improper' or incomplete roughing or vtreatment of the tube ends, as is Well recognized and familiar in the art. i

The present invention is directed to the elimination of this step of roughing or otherwise preparing the end or ends of tire tubes for splicing or joining, after the tubes are cured or vulcanized and removed from the tube mandrel, by the pro-vision of a method of forming tire tubes in which an end or the ends'of a tube are roughened or prepared for splicing during tie operation of vulcanizing or curing the tube on the mandrel or pole, so that the tube ends are prepared for splicing or joining upon stripping or removal of the vulcanized tube from the mandrel. ,y

. Another object of the invention is to provide a method of forming tire tubes in Which the step of'roughing. or preparing the tube ends for splicing after curing and removal of the tube from the mandrel, is eliminated, by preparing the tube ends for splicing dur ingy the Wrapping and vulcanizing operation of the tube` on the mandrel, `and While the vrubber is in a plastic, readily inoldable state.

Another object of the invention is to provide a method of forming tire tubes in which the `tube ends are roughenedk or prepared for splicing by molding the same on the mandrel or tube pole with the tube rubber in a plastic state and during the vulcanizing of thev tube, so as to eliminate preparation of the tube ends after vulcanization and removal of the tube from the mandrel, and

' to produce uniformity in the preparatifim of the tube ends and thereby reducethe num-- ber of defective splices, While increasingr production and reducing the cost thereof.

A further object. of the invention is the provision of simple and efficient apparatus for carrying out the method of the present invention, andto so design and arrange such apparatus that it Will noty only prepare the tube ends for splicing during and by the vulcanization of the tube, but'will further function to assist in Wrapping or binding the sheet rubber in tube `forming posi on the mandrel or pole,k

lith the foregoingv general objects and certain other objects in view, which other objects will be readily apparent to those skilled in the art from the 'following ex planation, the invention consists in certain novel steps in the method of 'tire tube manufacture, and in certain novel features in construction and in arrangements of the ele ments of apparatus therefor, as will be more fully and particularly referred to and specilied hereinafter. y

Referring' to the accompanying drawings:

Figi'. l, ,is a vieiv in elevation of a -tube mandrel or pole constructed in accordance with the invention.

Figi'. a rien' in elevation of the tube end ciainp oiE the invention 'tor binding' the lube to the pole and molding` the end oix the lube on theA ou thereolf into roughened ot linurled torni.

iiig'. l, `is a tragiinentary view in elevation et the liiiuried or roughened molding,` surface of the tube end clamp.

Fie'. lf, is a ievv in elevation showing` a Sheet et rubber Wound-onto the mandrel to torni the tube and clamped at one end by the end clamp ot the invention.

Fig'. 5, is a view in elevation similar to with the wraplrneA applied to the and the tube prepared 'tor vuleaniziiug;e

t3, is a vie-W in elevation of the rui.-

` canized tire tube stripped from the mandrel i h the ends knurled or roughened, one on the i eide the other on the outside, for splicine'.

Fie. T, a 'vieu' in elevation ot the prepared tube ends in eplieed petition to forni the completed tire tube.

In accordrliee with the present invention, a tube mandrel or pole i0 of the usual or any other desired e'elfieral type adapted for uae in the nianutzufture of tire tubes, is formed adjacent one end thereofT with a pertion el the outrsurt'aee knu'rled lor otherwise suitably roughened, to lorni a knul-led molding' baud ll completely afound the nuuulrel. The width and the location ot the lrniu'leti mandrel encircling` surtace or baud ll ou the mandrel` is auch that when the sheet or iu'ivulcanized rubber is wound into tube forming' iliosition on the mandrel, one end olf the lube overlaps this roue'hened o1' ltnurled portion with the inner.' eurl'ace ot the tube bearing tliereaeainst. The extent ot overlap ot the lube end onto th rouehened or ltnurled portion llV ol the mandrel ie approximately equal lo the lap of the splice desired when the. vulcanized tube ends 4are joined or `spliced to coi'n'plete. the tube,A and the purpose of the tube end overlapping onto surface 1l to f rm the desired roug'liened inner end surface of the tube `torthe splicing; operation,l as will be explained more jrully hef einaiter.

,t clamp l2 is provided, Figs. 2 and 3) for i'itting over and around Vthe end ol a tube on mandrel YlO opposite that overlappinp` mandrel band ll, for the purpose ot preparing the outer surface of the tube end for splicing, as by forming a roughened or knurled outerend surface therearound, as Well as for the purpose of clamping Vand securing` the end ot the tube `1to1-med by Winding the sheet rubber on the mandrel. in position `tor vulcanizing. The clamp l2 embodies a split ring or band of a suitable ,spring` or resilient mz-iterial, such for example as steel or braise, having` its inner surface lfl roughened or ltnurled completely therearound, as will be clear by reference to Figg in particular. The open or split ends' of the ring or band of clamp lf2 are, in the example hereof connected'together by ay lever type 'oi closure or lock l5 for drawing the ende ot the band together to clamp and loci; the band in clamping' position, or for releae ing;` the clamp l2 by spreading` the ende thereof to permit of its removal from clamping position. Aany suitable or desired means may be provided for securingl the clamp in operative position and for releasing' the same, as will be readily apparent. rlhe band iiol'niii'lg clamp l2 is of a Width to tit over and overlap the end of a tube a distance to form the refplired vwidth oit roughened tube end for the splice with the tube endeI joined In carrying out the method of the inventionwith the apparatus therefor, as above described, a sheet ont unvulcanized rubber ift is rolled or Weund onto the mandrel lO into tube forming position with one end thereof overlapping the lnurled band l1 'formed around the mandrel. A clamp 12 is then fitted over the mandrel and clamped onto and around the opposite end oit the sheet rubber R With the knurled Surface of the clamp bearing against and around the outer surface of the end of the tube .so formed, as Well as clamping` the end of the tube tightly against the mandrel to secure the rubber thereon and prevent paesage ot air or steam between the` end of'the tube and the mandrel. The "toregoinpV position ot the Wound .sheet rubber it and lube end clamp 12, is shown in Figi'. 1; oi the drawings. After the application ot end clanip l2, a strip or band of fabric F then spirally wrapped over'l the opposite end ol' the Wound rubber sheet lt forming' the tube which overlaps lnurled band ll oi the mandrel, and this spi al Wrapping of l'abric it is continued inwardly over and covering the unvulcanized tube to bind and .secure the saine in position on the mandrel 10, as Will be readily understood by those familiar With this art upon reference to Fig. 5 ofthe drawings,

The tube formed by the rubber sheet R Wound on mandrel l() and secured thereon in tube forming position by clamp 12 and Wrapped fabric F, is placed in any Suitable mtl llt)

ness-,e790

vulcanicr Aand is cured to produce the vulcanized tibe. AAs' the rubber'sheet R' is unvilllcanized and in' a plastic and readily'mo'l'dable or workable state before vu'lcaniaation, the inner surface of the end overlapping the lniurled band 11 aroundmandrel 10, and the outer surface of theend around which clamp 12 is secured with the sui-tace 14 thereof in Contact therewith, are molded or pressed rby these knurled 'surfaces which are forced thereagainst under pressure, and during vulcanization or curing ot the tube on the mandrel the opposite ends ot the tube are termed with the roughened or lmurled surtaces,.on the inner surilace ot the tube at one end and on and around the outer surface of the tube at the opposite end.H

After vulcanization on mandrel l0, the iliabric wrapping F and the end clamp 12 are removed, and the vulcanized tube T so formed, is stripped from the mandrel or pole in the usual or any other manner desired. The stripping operation reverses the inner and outer surfaces of the tube on the mandrel, so that on the stripped tube T, the roughened or knurled surface 16 :formed by the mandrel knurling 11 is around the outer surface of one end ot the tube, and the roughened surface 17 formed by the clamp 12 is around the inner surface ot the opposite end of the tube. A suitable cement or the like can then be applied to the roughened or knurled end surfaces 16 and 17, and the ends of the tube T brought together with the end otthe tube having the inner knurled surface 17 fitting over and lapping the end having the outer knurled surfacer 16, to'orm the tube splice, which is then vulcanized or otherwise suitably treated to secure and join the ends ot t-he tube together to form and complete the endless tire tube, as clearly shown by Fig. 7 of the accompanying drawings. i

Thus, the vulcanized tube T when stripped from the mandrel has its ends prepared for splicing or joining Without further opera-` tions thereon, and the step of preparing the tube ends for splicing after vulcanization and stripping -from the mandrel is climi naled. It desired or found expedient but one end of the tube need be roughened or prepared tor splicing. The apparatus for carrying out the method, and particularly the tubo end clamp 12, reduces the operation ot wrapping thc unvulcanized tube with .tabric F over both. ends and turther reduces the time and labor involved in the formation ot a tube.

In the foregoing description and eX- planation ot the invention, and in the accompanying drawings, a method oi' orming tire tubes embodying the steps ot' the method ot the invention, is presented in which the uneured tubes is formed on the curing mandrel by Winding a sheetot unrrestrictcdto themanner of forming yor placing *theL unvulcanized tube'on ay mandrel, as

the tube can be' formed in atuibing machine and then slipped onto the ymandrei, yor

Vblown onto the mandrel*byeoifnpressed air,

or in any other desired manner, Without going beyond the limits of the invention. Further, the invention is not limited to any particular means or method for obtaining pxssures on the tub-es during vulcanization, and the use ot fabric Wrapping as described and disclosed herein is purely by Way of example tor purposes of explanation and not by Way of limit-ation.

Vlfhile the method and apparatus ot the invention is particularly adapted for the format-ion of tire tubes, it is of general application 'to the formation oit other tubing tor `other purposes. The disclosure herein oi the straight, pole type of mandrel is not by Way of limitation as the invention is also capable of use in forming tubes on curved or other :terms of mandrels, as WillA be understood by those familiar With the art.

rlhe terms roughened or knurled as they are used herein and in the appended claims are to be interpreted in a generic sense to include any formation of the tube ends in preparation tor joining and splicing the same.

lt is also evident that various changes, variations, and modilications might be resorted to, and hence I do not Wish to limit inyseli1 to the exact disclosures hereot.

Desiring to protect myv invention in the broadest manner legally possible, what I Claim is:

1. In a method of forming tubes, those steps which consist in preparing the outer surface at one end ot the tube and the inner surface at the oppositeend of the tube during vulcanization to provide roughened contact s rfaces, for splicing" after vulcanization with the prepared ends overlapped.

2. In a method ot forming tubes, those steps which consist in forming a tube of unvulcanized rubber on a mandrel with one end thereof overlapping a roughened surtace around the n'landrel, applying a band having a roughened inner surface around the opposite end ot' the tube, applying pressure to the tube at the end overlapping the roughened mandrel surface, and then vulcanizing theV tube to prov-ide a vulcanized tube having the ends roughened tor overlapping and splicing.

3. In appara-tus for forming tire tubes, a tube mandrel having a lnurled band therearound for overlapping by the end ot an unvulcanized tube termed on the mandrel.

1l. Tn apparatus for forming tire tubes, in combina-tion, a tube mandrel having a knurled surface therearound for overlapping by an end of an unvuloanized tube formed on the mandrel, and a band having :L knurled inner surface for clamping around 5 the opposite end of the unvuleunized tube on said mandrel.

5. As a new article of manufacture, a

tire tube formed with :L knurled surface around the inner side of one end thereof, und zr knurled Surface around the outer Side I0 of the opposite end thereof.

Signed at Racine, Racine County, YVisconsin7 this 12th day of May, 1926.

JOHN WV. AUMAN. 

